OK...so I put my gravid iguana, Igby, in a 4 foot by 3 foot nesting box with at least a foot of sand/dirt substrate. She has a hot spot of about 95 degrees, and cooler spots of about 80. Night temps are similar, maybe just a bit cooler. She has not eaten well in three weeks. Igby has dug several holes, but has not appeared to have laid any eggs. How long of a process is this? How do I know if she is eggbound? She is in one place all the time, under the heat, but is still active when I come by to feed her or spray her. Any advice is greatly appreciated.

I'm not overly familiar with ig laying behaviour, but I do know our leopard and fattailed geckos often dig for a week or more before laying their eggs. We had one girl visibly gravid and digging for over two and a half weeks before she finally laid her eggs, and she's doing fine.
We've also noticed that they tend to flatten their eggy bellies on the warmest spot available -- it's probably the same with Igby. Considering when they actually ARE eggbound a warm bath can help trigger laying, it's probably a natural instinct to warm their bellies and help the process along.
Check out this link, it has a good gestation timeline:
http://www.anapsid.org/iguana/egging.html#gestate

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I give up! I've officially lost count of the critters...

My female will go through about a month of not eating, scratching and digging and wanting out. She stops eating completely a couple of weeks before egging.
Since she gets most of her water from her food she may become dehydrated. Try spraying a gentle stream of water on the front of her mouth from a plant misting bottle and see if she will lick the water. When they finally do lay you will know it since they will look like a deflated balloon. Keep a close eye on her for any yellowing of her gcolor and any listless behavior.
I gather this is your first experience with a gravid iguana? You really need to consult with your vet to make sure that she IS gravid and that there are no problems.
If you even SUSPECT that your iguana is eggbound you need to have her seen by a vet, immediately.

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Merlin,
What's Life Without A Little Magic!

Yes, this is my first experience with a gravid iguana. We did take her to the vet two weeks ago to confirm that she was gravid. We have since tried to follow every rule for her to lay eggs, including warm baths, calcium supplements, etc. I was just wondering how long it takes. The website provided in one of the responses was very informative. Thank you for any other responses, advice, or anecdotal stories to help us out! I truly appreciate it!

It's a really tough call when they are gravid.

You should certainly have a vet perform an x-ray on her to determine if all the eggs are well formed and that there is no blockage occurring that is preventing laying.

We just had a female iguana go gravid, confirmed by initial x-ray. Many weeks later, and after 3 weeks of not eating and looking extremely uncomfortable, she went back to the vet. The vet took more x-rays. The results were startling and she required immediate surgery and spay!

The eggs had not properly formed. They formed into kinda like one long egg mass, looked more like very big intestines than eggs. This was preventing her from laying out. Had she not gone to the vet and had another x-ray, it might have cost her her life. I have the eggs in formaldehyde and they are about the strangest eggs I ever saw. There is no beginning or end to them.

So as not to be an alarmist here, many iguanas take weeks to lay out and are just fine doing so. But, if you see that her behavior suddenly changes, or she seems terribly uncomfortable, you may want to get her to a vet for an x-ray.

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Regards,
Dominick
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